1. Field of the Invention
The present invention relates to an arrangement for a continuous two-stage ejector of the built-in type for moulding tools comprising pairs of front and rear moving ejector plates and an actuating device for causing the aforementioned ejector plates to be moved to intended positions.
2. Description of Related Art
Previously disclosed two-stage ejectors of the kind that are intended for building-in are designed as a rule so that a bridge part, which is attached between ejector plates of the kind in question, runs in a slotted guide and stop sleeve and constitutes the basis for the two-stage function. Bridge parts of this kind and long sleeve parts that are slotted are expensive to manufacture and are difficult to build into the tool in question. The previously disclosed two-stage ejectors must also be secured against rotation with rotation-preventing means, which increases the cost.
The principal object of the present invention is,
In the first instance, to attempt to solve the aforementioned problems by simple and reliably functioning means in conjunction with a moulding machine essentially for the manufacture of plastic components, but also for metal-forming machines.
The aforementioned object is achieved by means of an arrangement in accordance with the present invention, which is characterized essentially in that front ejector plates are attached to, and are capable of actuation by, a reciprocating rod that is connected to the machine, in that a central pin extends between the fixed plate of the moulding tool and the body of the moulding tool, in that the aforementioned central pin exhibits an annular groove at a distance from a projection on the aforementioned central pin, in that pairs of sleeves are accommodated by the aforementioned central pin with one sleeve passed onto the other sleeve, in that each of the two sleeves is attached to its own moving ejector plate, in that the inner sleeve exhibits transcurrent recesses corresponding to the desired number of locking segments, in that the outer sleeve exhibits a stop part capable of actuating the aforementioned locking segments, in that the aforementioned locking segments exhibit accommodating parts capable of interacting with the aforementioned grooves, in that extension of the first sleeve is restricted by the projection, in conjunction with which the ejector of the moulding tool is so arranged in an initial phase as to actuate the front ejector plates and so that the rear ejector plates are conveyed along through the interconnection of the two sleeves with the help of the locking segments, and in that, after actuation of the locking segments and their accommodation in the aforementioned annular groove, the rear ejector plates are released and the front ejector plates are so arranged as to be actuated singly by the ejector causing them to be extended to the intended end position.